Potterton Gold H Range User guide

1
UNVENTED MAINS PRESSURE WATER HEATERS
100, 120, 150, 170, 210, 250 and 300 LITRE CAPACITY DIRECT AND
INDIRECT MODELS INSTALLATION AND SERVICING INSTRUCTIONS
PACK CONTENTS
The POTTERTON GOLD unvented water heater incorporating immersion heater(s) and thermal controls
l Factory tted temperature/pressure relief valve l Cold water combination valve assembly
l Expansion vessel and mounting bracket l Tundish l Motorised valve (indirect models only) l
Compression nuts and olives l Immersion heater spanner l Installation instructions
IMPORTANT: PLEASE READ AND UNDERSTAND THESE INSTRUCTIONS
BEFORE COMMENCING INSTALLATION. PLEASE LEAVE THIS MANUAL
WITH THE CUSTOMER FOR FUTURE REFERENCE.
INTRODUCTION
The POTTERTON GOLD cylinder is a purpose designed
unvented water heater.The unit has a stainless steel inner
vessel, which ensures an excellent standard of corrosion
resistance. The outer casing is a combination of resilient
thermoplastic mouldings and plastic coated corrosion
proofed steel sheet. All products are insulated with CFC
free polyurethane foam to give good heat loss
performance. ( See Table 6 )
The unit is supplied complete with all the necessary
safety and control devices needed to allow connection
to the cold water mains. All these components are preset
and not adjustable.
NOTE: Prior to installation the unit should be stored
in an upright position in an area free from excessive
damp or humidity.
This appliance complies with the requirements of
the CE marking directive and is Kiwa approved to
show compliance with Building Regulations
(Section G3).
The following instructions are oered as a guide
to installation which must be carried out by a
competent plumbing and electrical installer in
accordance with Building Regulation G3, The
Building Standards (Scotland) Regulations 1990, or
The Building Regulations (Northern Ireland).
THE BENCHMARK SCHEME
Benchmark places responsibilities on both manufacturers and installers. The purpose is to ensure that customers
are provided with the correct equipment for their needs, that it is installed, commissioned and serviced in
accordance with the manufacturer’s instructions by competent persons and that it meets the requirements of
the appropriate Building Regulations. The Benchmark Checklist can be used to demonstrate compliance with
Building Regulations and should be provided to the customer for future reference.
Installers are required to carry out installation, commissioning and servicing work in accordance with the
Benchmark Code of Practice which is available from the Heating and Hotwater Industry Council who manage
and promote the Scheme. Visit www.centralheating.co.uk for more information.
IMPORTANT NOTE TO USER: PLEASE REFER TO THE USER INSTRUCTIONS SECTION ON PAGES 19 AND 20 FOR
IMPORTANT INFORMATION WITH RESPECT TO THE BENCHMARK SCHEME

2
Contents
INTRODUCTION.................................................................1
GENERAL REQUIREMENTS.............................................3
INSTALLATION-GENERAL...............................................4
INSTALLATION...................................................................10
COMMISSIONING.............................................................13
MAINTENANCE..................................................................14
USER INSTRUCTIONS.......................................................15
FAULT FINDING AND SERVICING.................................16
HEAT LOSS...........................................................................18
ENVIRONMENTAL INFORMATION...............................18
COMMISSIONING CHECK LIST......................................19
SERVICE RECORD..............................................................20
GUARANTEE.......................................................................21
TECHNICAL SUPPORT AND SPARES...........................24
PAGE

3
SITING THE UNIT
The POTTERTON GOLD cylinder must be vertically
oor mounted. Although location is not critical, the
following points should be considered:
• ThePOTTERTONGOLDcylindershouldbesited
to ensure minimum dead leg distances, par-
ticularly to the point of most frequent use.
• Avoidsitingwhereextremecoldtemperatures
will be experienced. All exposed pipe work
should be insulated.
• Thedischargepipeworkfromthesafetyvalves
must have minimum fall of 1:200 from the unit
and terminate in a safe and visible position.
• Accesstoassociatedcontrolsandimmersion
heaters must be available to provide for the
servicing and maintenance of the system.
Where these controls are installed against a wall
a minimum distance of 250mm must be left
(see Fig. 1).
• EnsurethattheoorareaforthePOTTERTON
GOLDcylinderislevelandcapableofpermanently
supporting the weight when full of water.
(see Table 1)
WATER SUPPLY
Bear in mind that the mains water supply to the
property will be supplying both the hot and cold
water requirements simultaneously. It is recom-
mended that the maximum water demand is
assessed and the water supply checked to ensure
this demand can be satisfactorily met.
Note: A high mains water pressure will not always
guarantee high ow rates.
Wherever possible the mains supply pipe should be
22mm. We suggest the minimum supply require-
ments should be 1.5 bar pressure and 20 litres per
minute owrate. However, at these values outlet
ow rates may be poor if several outlets are used
simultaneously.The highertheavailablepressure and
ow rate the better the system performance.
The POTTERTON GOLD cylinder has an operating
pressure of 3.5 bar which is controlled by the cold
water combination valve assembly. The cold water
combination valve assembly can be connected to a
maximum mains pressure of 16 bar.
OUTLET/TERMINAL FITTINGS (TAPS, ETC.)
The POTTERTON GOLD cylinder can be used with
most types of terminal ttings. It is advantageous
in many mixer showers to have balanced hot and
cold water supplies. In these instances a balanced
pressure cold water connection should be placed
between the 2 pieces of the cold water combination
valve assembly (see Fig.2). Outlets situated higher
than the POTTERTON GOLD cylinder will give
outlet pressures lower than that at the heater, a
10m height dierence will result in a 1 bar pressure
reduction at the outlet. All ttings, pipework and
connections must have a rated pressure of at least
6 bar at 80°C.
Table 1: Unit weights
Fig. 1: Siting the Unit
Type Capacity
(litres)
Weight of full
unit (kg)
120
100
150
170
210
Indirect
147
125
181
204
257
250
300
300
360
Direct
120
100
150
170
210
250
300
146
124
179
201
252
295
355
WALL
Min 250mm Min 250mm
GENERAL REQUIREMENTS
IMPORTANT: THIS APPLIANCE IS NOT INTENDED
FOR THE USE BY PERSONS (INCLUDING CHILDREN)
WITH REDUCED PHYSICAL, SENSORY OR MENTAL
CAPABILITIES, OR LACK OF KNOWLEDGE AND
EXPERIENCE, UNLESS THEY HAVE BEEN GIVEN
SUPERVISION OR INSTRUCTION CONCERNING
THE USE OF THE APPLIANCE BY A PERSON
RESPONSIBLE FOR THEIR SAFETY. CHILDREN MUST
BE SUPERVISED.

4
INSTALLATION  GENERAL
SEE FIGS. 2  6
PIPE FITTINGS
All pipe ttings are made via 22mm compression
ttings directly to the unit.The ttings are threaded
3/4”BSP male parallel should threaded pipe connec-
tions be required.
COLD FEED
A 22mm cold water supply is recommended, how-
ever, if a 15mm (1/2”) supply exists, which provides
sucientow, this may be used (although more ow
noise may be experienced).
A stopcock or servicing valve should be incorporated
into the cold water supply to enable the POTTERTON
GOLD cylinder and its associated controls to be
isolated and serviced.
COLD WATER COMBINATION VALVE ASSEMBLY (FIG.
2)
The 2-piece cold water combination valve assembly
can be located anywhere on the cold water mains
supply prior to the expansion vessel ( see Fig. 6 Page
9 ) but the two pieces do not have to be installed
together.
Fig. 2: Cold water combination valve assembly
DRAIN TAP
A suitable draining tap should be installed in the cold
water supply to the POTTERTON GOLD cylinder
between the expansion valve ( see Fig. 6 Page 9 )
and the heater at as low a level as possible. It is
recommended that the outlet point of the drain
pipework be at least 1 metre below the level of the
heater (this can be achieved by attaching a hose to
the drain tap outlet spigot).
EXPANSION VESSEL
The expansion vessel accommodates expansion
that results from heating the water inside the unit.
The expansion vessel is pre-charged at 3.5 bar. The
expansion vessel must be connected between the
expansion valve (see Fig. 2) and the POTTERTON
GOLD cylinder ( see Fig. 6 Page 9 ).The location of the
expansion vessel should allow access to recharge the
pressure as and when necessary, this can be done
using a normal car foot pump. It is recommended
that the expansion vessel is adequately supported.
An expansion vessel wall mounting bracket is
supplied for this purpose and should be tted.
OPERATIONAL SUMMARY
Maximum mains pressure 16 bar
Operating pressure 3.5 bar
Expansion vessel charge pressure 3.5 bar
Expansion relief valve setting 6 bar
T&P relief valve setting 90°C/10 bar
Maximum primary circuit pressure 3 bar
(indirect only)
Storage capacity See Table1
Weight when full See Table1
LIMITATIONS
The POTTERTON GOLD cylinder should not be used
in association with any of the following:
• Solidfuelboilersoranyotherboilerinwhich
the energy input is not under eective
thermostatic control, unless additional and
appropriate safety measures are installed.
• Ascendingspraytypebidetsoranyother
class 1 back syphonage risk requiring that a type
A air gap be employed.
• Steamheatingplantsunlessadditionaland
appropriate safety devices are installed.
• Situationswheremaintenanceislikelytobe
neglected or safety devices tampered with.
• Watersuppliesthathaveeitherinadequate
pressure or where the supply may be intermittent.
• Situationswhereitisnotpossibletosafely
pipe away any discharge from the safety valves.
•Inareaswherethewaterconsistentlycontainsa
high proportion of solids, e.g. suspendedmatter
that could block the strainer, unless adequate
filtrationcanbeensured.
The pressure reducing valve incorporates the
pressure reducer and strainer and the expansion valve
incorporates the expansion and check valves. Ensure
that the valves are installed in the correct order
and orientation. No other valves should be placed
between the expansion valve and the POTTERTON
GOLD cylinder. A connection can be made between
the expansion and pressure reducing valves to
provide a balanced cold water connection. The
expansion valve connection must not be used for
any other purpose.
SECONDARY CIRCULATION
If secondary circulation is required it is recommended
that it be connected to the POTTERTON GOLD
cylinder as shown in Fig. 3 via a swept tee joint into
the cold feed to the unit. A swept tee joint is available
as an accessory (order code no. 5133565).
The secondary return pipe should be in 15mm pipe
and incorporate a check valve to prevent backow.
A suitableWRAS approved bronze circulation pump
will be required. On large systems, due to the

5
Fig. 3: Secondary circulation connection
OUTLET
The hot water outlet is a 22mm compression tting
located at the top of the cylinder. Hot waterdistribution
pipework should be 22mm pipe with short runs of
15mm pipe to terminal ttings such as sinks and
basins. Pipe sizes may vary due to system design.
increase in system water content, it may be necessary
to t an additional expansion vessel to the secondary
circuit. This should be done if the capacity of the
secondary circuit exceeds 10 litres.
Pipe capacity (copper):
15mm O.D. = 0.13 l/m (10 litres = 77m)
22mm O.D. = 0.38 l/m (10 litres = 26m)
28mm O.D. = 0.55 l/m (10 litres = 18m)

6
Fig. 4 General dimensions
Notes:
1. Heat up time from cold through 45°C, with a primary ow rate 15ltrs/min at 80°C.
2. Recovery time based on heating 70% of capacity through 45°C.
3. Direct heating times assume use of lower element only, from cold, through 45°C.
Table 2: Dimensions and performance
COIL
DIMENSIONS (mm)
NOMINAL
CAPACITY
(litres)
A B C D RATING
(kW)
RECOVERY
(mins)
HEATING TIME
DIRECT (mins)
100
120
120
150
315 364 615 906
364 800 1090
315 364 925 1216
364 1184 1474
12.5 23
89
100
364 493 784 89
110
110
142
142
163
1731
2045
1378
1693
364
364
315
150
170
HEAT UP
TIME (mins)
27
210
210
250
250
364 615 906
315 364 800 1090
364 925 1216
315 364 1184 1474
12.5 24
16.0 29
205
170
315 364 493 784
11.2 20
163
205
252
252
304
304
35
19.0
1731
2045
1378
1693
364
364
315
300
300
38
41
26
47
Direct Indirect
TYPE
30
18.0 40
16.0 2533

7
DISCHARGE PIPEWORK
It is a requirement of Building Regulation G3
that any discharge from an unvented system
is conveyed to where it is visible, but will not
cause danger to persons in or about the building.
The tundish and discharge pipes should be
tted in accordance with the requirements and
guidance notes of Building Regulation G3.The G3
Requirements and Guidance section 3.50 - 3.63
are reproduced in the following sections of
this manual. For discharge pipe arrangements
not covered by G3 Guidance advice should be
sought from your local Building Control Ocer.
Any discharge pipe connected to the pressure
relief devices (Expansion Valve and Temperature/
Pressure Relief Valve) must be installed in a
continuously downward direction and in a frost
free environment.
Water may drip from the discharge pipe of the
pressure relief device. This pipe must be left open
to the atmosphere. The pressure relief device is
to be operated regularly to remove lime deposits
and to verify that it is not blocked.
G3 REQUIREMENT
“...there shall be precautions...to ensure that the
hot water discharged from safety devices is safely
conveyed to where it is visible but will not cause
danger to persons in or about the building.”
The following exract is taken from the latest G3
Regulations
Discharge pipes from safety devices
Discharge pipe D1
3.50 Each of the temperature relief valves or combined
temperature and pressure relief valves specied in 3.13 or
3.17 should discharge either directly or by way of a mani-
fold via a short length of metal pipe (D1) to a tundish.
3.51 The diameter of discharge pipe (D1) should be not
less than the nominal outlet size of the temperature relief
valve.
3.52 Where a manifold is used it should be sized to accept
and discharge the total discharge form the discharge pipes
connected to it.
3.53 Where valves other than the temperature and pres-
sure relief valve from a single unvented hot water system
discharge by way of the same manifold that is used by the
safety devices, the manifold should be factory tted as part
of the hot water storage system unit or package.
Tundish
3.54 The tundish should be vertical, located in the same
space as the unvented hot water storage system and be t-
ted as close as possible to, and lower than, the valve, with
no more than 600mm of pipe between the valve outlet and
the tundish (see Diagram 1).
Note: To comply with the Water Supply (Water Fittings)
Regulations, the tundish should incorporate a suitable air
gap.
3.55 Any discharge should be visible at the tundish. In
addition, where discharges from safety devices may not
be apparent, e.g. in dwellings occupied by people with
impaired vision or mobility, consideration should be given
to the installation of a suitable safety device to warn when
discharge takes place, e.g. electronically operated.
Discharge pipe D2
3.56 The discharge pipe (D2) from the tundish should:
(a) have a vertical section of pipe at least 300mm long
below the tundish before any elbows or bends in the pipe-
work (see Fig. 5); and
(b) be installed with a continuous fall thereafter of at
least 1 in 200.
3.57 The discharge pipe (D2) should be made of:
(a) metal; or
(b) other material that has been demonstrated to be
capable of safely withstanding temperatures of the water
discharged and is clearly and permanently marked to
identify the product and performance standard (e.g. as
specied in the relevant part of BS 7291).
3.58 The discharge pipe (D2) should be at least one pipe
size larger than the nominal outlet size of the safety device
unless its total equivalent hydraulic resistance exceeds that
of a straight pipe 9m long, i.e. for discharge pipes between
9m and 18m the equivalent resistance length should be at
least two sizes larger than the nominal outlet size of the
safety device; between 18 and 27m at least 3 sizes larger,
and so on; bends must be taken into account in calculat-
ing the ow resistance. See Fig 1, Table 3 and the worked
example.
Note: An alternative approach for sizing discharge pipes
would be to follow Annex D, section D.2 of BS 6700:2006
Specication for design, installation, testing and mainte-
nance of services supplying water for domestic use within
buildings and their curtilages.
3.59 Where a single common discharge pipe serves more
than one system, it should be at least one pipe size larger
than the largest individual discharge pipe (D2) to be con-
nected.
3.60 The discharge pipe should not be connected to a soil
discharge stack unless it can be demonstrated that that
the soil discharge stack is capable of safely withstanding
temperatures of the water discharged, in which case, it
should:
(a) contain a mechanical seal, not incorporating a water
trap, which allows water into the branch pipe without al-
lowing foul air from the drain to be ventilated through the

8
tundish;
(b) be a separate branch pipe with no sanitary appli-
ances connected to it;
(c) if plastic pipes are used as branch pipes carrying
discharge from a safety device they should be either polyb-
utalene (PB) to Class S of BS 7291-2:2006 or cross linked
polyethylene (PE-X) to Class S of BS 7291-3:2006; and
(d) be continuously marked with a warning that no
sanitary appliances should be connected to the pipe.
Note:
1. Plastic pipes should be joined and assembled with
ttings appropriate to the circumstances in which they are
used as set out in BS EN ISO 1043-1.
2. Where pipes cannot be connected to the stack it may
be possible to route a dedicated pipe alongside or in close
proximity to the discharge stack.
Termination of discharge pipe
3.61 The discharge pipe (D2) from the tundish should
terminate in a safe place where there is no risk to persons
in the vicinity of the discharge.
3.62 Examples of acceptable discharge arrangements are:
(a) to a trapped gully with the end of the pipe below a
xed grating and above the water seal;
(b) downward discharges at low level; i.e. up to 100mm
above external surfaces such as car parks, hard standings,
grassed areas etc. are acceptable providing that a wire
cage or similar guard is positioned to prevent contact,
whilst maintaining visibility; and
(c) discharges at high level: e.g. into a metal hopper
and metal downpipe with the end of the discharge pipe
clearly visible or onto a roof capable of withstanding high
temperature discharges of water and 3m from any plastic
guttering system that would collect such discharges.
3.63 The discharge would consist of high temperature
water and steam. Asphalt, roong felt and non-metallic
rainwater goods may be damaged by such discharges.
Worked example of discharge pipe sizing
Fig. 5: shows a G1/2 temperature relief valve with a
discharge pipe (D2) having 4 No. elbows and length of
7m from the tundish to the point of discharge.
From Table 3:
Maximum resistance allowed for a straight length of
22mm copper discharge pipe (D2) from a G1/2
temperature relief valve is 9.0m.
Subtract the resistance for 4 No. 22mm elbows at 0.8m
each = 3.2m
Therefore the permitted length equates to: 5.8m
5.8m is less than the actual length of 7m therefore
calculate the next largest size.
Maximum resistance allowed for a straight length of
28mm pipe (D2) from a G1/2 temperature relief valves
equates to 18m.
Subtract the resistance of 4 No. 28mm elbows at 1.0m
each = 4.0m
Therefore the maximum permitted length equates to:
14m
As the actual length is 7m, a 28mm (D2) copper pipe
will be satisfactory.
WARNINGS:
• Under no circumstances should the factory
tted temperature/pressure relief valve be
removed other than by a competent
person. To do so will invalidate any
guarantee or claim.
• Thecoldwatercombinationvalveassembly
must be tted on the mains water supply to
the POTTERTON GOLD cylinder.
• Nocontrolorsafetyvalvesshouldbetampered
with or used for any other purpose.
• Thedischargepipeshouldnotbeblockedor
used for any other purpose.
• Thetundishshouldnotbelocatedadjacent
to any electrical components.
Table 3: Sizing of copper discharge pipe (D2) for common temperature relief valve outlet sizes
NOTE: The above table is based on copper tube. Plastic pipes may be of dierent bore and resistance. Sizes and
maximum lengths of plastic should be calculated using data prepared for the type of pipe being used.
VALVE OUTLET
SIZE
MINIMUM SIZE OF
DISCHARGE PIPE D1
MINIMUM SIZE OF
DISCHARGE PIPE D2
FROM TUNDISH
MAXIMUM RESISTANCE
ALLOWED, EXPRESSED
AS A LENGTH OF
STRAIGHT PIPE (I.E. NO
ELBOWS OR BENDS
RESISTANCE CREATED BY
EACH ELBOW OR BEND
G 1/2 15MM 22mm
28mm
35mm
UP TO 9M
UP TO 18M
UP TO 27M
0.8M
1.0M
1.4M
G 3/4 22MM 28mm
35mm
42mm
UP TO 9M
UP TO 18M
UP TO 27M
1.0M
1.4M
1.7M
G 1 28MM 35mm
42mm
54mm
UP TO 9M
UP TO 18M
UP TO 27M
1.4M
1.7M
2.3M

9
Fig. 5: Typical discharge pipe arrangement (extract from Building Regulation G3 Guidance section 3.50)
Fixed grating
Discharge below
fixed grating
(Building Regulation
G3 section 3.61 gives
alternative points
of discharge)
Trapped
gully
Discharge pipe (D2) from tundish,
with continuous fall. See Building
Regulation G3 section 3.56, Table 1
and worked example
300mm
minimum
600mm maximum
Metal discharge pipe (D1) from
Temperature relief valve to tundish
Tundish
Safety device
(e.g. Temperature
relief valve)
Fig. 6: Typical installation - schematic
EXPANSION
VESSEL
T&P RELIEF
VALVE
TO HOT
OUTLETS
MAINS
WATER
SUPPLY
ISOLATING
VALVE (NOT
SUPPLIED)
TUNDISH
DISCHARGE
PIPE
DRAIN COCK
(NOT SUPPLIED)
PRIMARY
RETURN
PRIMARY
FLOW
ELEMENT /
CONTROLS
HOUSING
INLET SECONDARY RETURN
TAPPING (IF REQUIRED)
NOT SUPPLIED
COLD WATER
COMBINATION
VALVE
(2-PIECE)
BALANCED
COLD WATER
CONNECTION
(IF REQUIRED)

10
Fig. 7: Electrical connections (schematic)
INDIRECT MODELS
12
GREEN/
YELLOW
13 AMP MAINS
SUPPLY. 1.5mm 2
MIN. CABLE SIZE
TO INDIRECT SYSTEM
CONTROLS JUNCTION
BOX - SEE FIGS. 8/9
GREEN/
YELLOW
BROWN
BLUE
3
DIRECT
THERMOSTAT
B
A
11 223
INDIRECT
THERMOSTAT
INDIRECT THERMAL
CUT-OUT
TERMINAL
BLOCK
DIRECT MODELS
BROWN
BLUE
GREEN/YELLOW
Note:On models fitted with two elements each element must be
wired individually in accordance with the diagram above.
THERMOSTAT
EARTH
CONNECTION
FUSED (13A) DOUBLE
POLE ISOLATING
SWITCH
A
B
1.5mm23 CORE
HOFR SHEATHED
CABLE
INSTALLATION  DIRECT UNITS
PLUMBING CONNECTIONS
POTTERTON GOLD direct cylinders require the fol-
lowing
pipework connections.
• Cold water supply to and from inlet controls.
• Outlet to hot water draw o points.
• Discharge pipework from valve outlets to
tundish
ELECTRICAL SUPPLY (FIG. 6)
100 litre direct Potterton Gold units are tted with
one 3kW immersion heater, all other direct mod-
els are tted with two 3kW immersion heaters as
standard. It is recommended that these should be
wired via a suitable controller to BSEN 60730. The
POTTERTON GOLD MUST be earthed.
All wiring to the unit must be installed in accordance
with the latest IEEWiring Regulations and the circuit
must be protected by a suitable fuse and double
pole isolating switch with a contact separation of
at least 3mm in both poles. The live and neutral
connections are made directly onto the combined
thermostat and thermal cut-out located under the
terminal cover(s) mounted on the side of the unit.
The earth connection should be made to the earth
connection located to the side of the immersion
heater boss(es). The supply cable must be routed
through the cable gland located on the unit casing
beneath the terminal housing.
DO NOT operate the immersion heaters until the
cylinder has been lled with water.
SAFETY
DISCONNECT FROM THE MAINS SUPPLY
BEFORE REMOVING ANY COVERS.
Never attempt to replace the immersion heater(s)
other than with the recommended Potterton Gold
immersion heater(s).
DO NOT BYPASS THE THERMAL CUT-OUT(S)
IN ANY CIRCUMSTANCES. Ensure the two
male spade terminations on the underside of the
combined thermostat and thermal cut-out are
pushed rmly onto the corresponding termina-
tions on the element plate assembly.
In case of difculty contact service support;
contact details available at the back of this
booklet.

11
INSTALLATION  INDIRECT UNITS
PLUMBING CONNECTIONS
POTTERTON GOLD indirect cylinders require the
following
pipework connections.
• Cold water supply to and from inlet controls.
• Outlet to hot water draw o points.
• Discharge pipework from valve outlets to
tundish
• Connection to the primary circuit.
All connections are 22mm compression. However,
3/4”BSP parallel threaded ttings can be tted to
the primary coil connections if required.
ELECTRICAL SUPPLY ( FIG. 7 Page 10 )
All units are tted with a 3kW immersion heater
and a combined thermostat and thermal cut-out to
control the indirect heating source. ThePOTTERTON
GOLD cylinder MUST be earthed.
All wiring to the unit must be installed in accordance
with the latest IEE Wiring Regulations and the
supply circuits must be protected by a suitable fuse
and double pole isolating switch with a contact
separation of at least 3mm in both poles. All
connections are made to the terminal block located
under the terminal cover mounted on the side of the
unit.The supply cable(s) must be routed through the
cable grip(s) in the terminal housing.
DISCONNECT FROM MAINS SUPPLY BEFORE
REMOVING ANY COVERS. DO NOT BYPASS THE
THERMAL CUTOUTS IN ANY CIRCUMSTANCES.
Ensure the thermostat and thermal cut-out sensing
bulbs are pushed fully into the pockets on the
element plate assembly.
BOILER SELECTION
The boiler should have a control thermostat and non
self-resetting thermal cut-out and be compatible
with unvented storage water heaters.
Where use of a boiler without a thermal cut-out
is unavoidable a “low head” open vented primary
circuit should be used. The feed and expansion
cistern head above the POTTERTON GOLD cylinder
should not exceed 2.5m.
PRIMARY CIRCUIT CONTROL
The 2 port motorised valve supplied with the
POTTERTON GOLD cylinder MUST be tted on the
primary flow to the POTTERTON GOLD cylinder
heat exchanger and wired in series with the indirect
thermostat and thermal cut-out tted to the unit.
Primary circulation to the POTTERTON GOLD
cylinder heat exchanger must be pumped; gravity
circulation WILL NOT WORK.
SPACE AND HEATING SYSTEMS CONTROLS
The controls provided with the POTTERTON GOLD
cylinder will ensure the safe operation of the unit
within the central heating system. Other controls
will be necessary to control the space heating
requirements and times that the system is required
to function. (See Fig. 7 Page 10)
The POTTERTON GOLD cylinder is compatible
with most heating controls, examples of electrical
circuits are shown in Figs. 8 and 9 ( Page 12 ).
However, other systems may be suitable, refer to
the controls manufacturers’ instructions, supplied
with the controls selected, for alternative system
wiring schemes.

12
Fig. 8: Schematic wiring diagram - Basic 2 x 2 port valve system
Fig. 9: Schematic wiring diagram - 3 port mid position valve system. N.B. Must be used in conjunction with 2 port
zone valve supplied

13
COMMISSIONING
At the time of commissioning, please ensure all
relevant sections of the Benchmark Checklist, (Page
19 and 20 ) of this document, are completed.
FILLING THE UNIT WITH WATER
• Checkexpansionvesselpre-chargepressure. The
vessel is supplied precharged to 3.5 bar to match
the control pressure of the pressure reducing
valve. The precharge pressure is checked using
a car tyre gauge by unscrewing the plastic cap
opposite the water connection.
• Check all connections for tightness including
the immersion heater(s). An immersion heater
key spanner is supplied for this purpose.
• Ensure the drain cock is CLOSED.
• Open a hot tap furthest from the POTTERTON
GOLD cylinder.
• Open the mains stop cock to fill the unit.
When water ows from the tap, allow to run for
a few minutes to thoroughly ush through any
residue, dirt or swarf, then close the tap.
• Open successive hot taps to purge the system
of air.
SYSTEM CHECKS
• Check all water connections for leaks and
rectify as necessary.
• Turn o mains water supply.
• Remove the pressure reducing valve head
work to access the strainer mesh, clean
and re-t.
• Manually open, for a few seconds, each
relief valve in turn, checking that water is
discharged and runs freely through the
tundish and out at the discharge point.
• Ensure that the valve(s) reseat
satisfactorily.
DIRECT UNITS
Switchonelectricalsupplytotheimmersionheater(s)
and allow the cylinder to heat up to normal working
temperature (60ºC recommended, approximately
graduation 4 on the thermostat). If necessary the
temperature can be adjusted by inserting a flat
bladed screwdriver in the adjustment knob on top of
the immersion heater thermostat and rotating. The
adjustment range 1 to 5 represents a temperature
range of 10oto 70oC. Check the operation of
thermostat(s) and that no water has issued from
the expansion relief valve or temperature/pressure
relief valve during the heating cycle.
Fig. 10: Indirect thermostat and thermal cut-out
THERMAL
CUT-OUT RESET BUTTON
THERMOSTAT
ADJUSTMENT
THERMOSTATTERMINAL BLOCK
CABLE
CLAMPS
THERMAL
CUT-OUT
NOTE: THE HOUSING COVER AND
ELEMENT ASSEMBLY HAVE BEEN REMOVED
FROM THIS VIEW FOR CLARITY
INDIRECT UNITS
Fill the indirect (primary) circuit following the
boiler manufacturer’s commissioning instructions.
To ensure the POTTERTON GOLD cylinder primary
heat exchanger is lled, the 2 port motorised valve
(supplied) should be manually opened by moving
the lever on the motor housing to the MANUAL
setting. When the primary circuit is full return the
lever to the AUTOMATIC position. Switch on the
boiler, ensure the programmer is set to Domestic
HotWater and allow the POTTERTON GOLD cylinder
to heat up to a normal working temperature (60oC
recommended, approximately graduation 4 on the
thermostat). If necessary the temperature can be
adjusted by inserting a at bladed screwdriver in the
adjustment knob (located on top of the thermostat
mounting bracket - see Fig.10 Page 13 ) and rotating.
The minimum thermostat setting is 10°C.
The adjustment range 1 to 5 represents a temperature
range of 30oto 70oC. Check the operation of the
indirect thermostat and 2 port motorised valve and
that no water has issued from the expansion relief
valve or temperature/pressure relief valve during
the heating cycle.

14
MAINTENANCE
MAINTENANCE REQUIREMENTS
Unvented hot water systems have a continuing
maintenance requirement in order to ensure safe
working and optimum performance. It is essential
that the relief valve(s) are periodically inspected and
manually opened to ensure no blockage has
occurred in the valves or discharge pipework.
Similarly cleaning of the strainer element and
replacement of the air in the expansion vessel will
help to prevent possible operational faults.
The maintenance checks described below should be
performed by a competent person on a regular basis,
e.g. annually to coincide with boiler maintenance.
After any maintenance, please complete the
relevant Service Interval Record section of the
Benchmark Checklist located on Page 19 and 20 of
this document.
SAFETY VALVE OPERATION
Manually operate the temperature/pressure relief
valve for a few seconds. Check water is discharged
and that it ows freely through the tundish and
discharge pipework. Check valve reseats correctly
when released. NOTE: Water discharged may be
very hot!
Repeat the above procedure for the Expansion
Valve.
STRAINER
Turn o the cold water supply, boiler and immersion
heaters. The lowest hot water tap should then be
opened to de-pressurise the system. Remove the
pressure reducing cartridge to access the strainer
mesh.Wash any particulate matter from the strainer
under clean water. Re-assemble ensuring the seal
is correctly tted. DO NOT use any other type of
sealant.
DESCALING IMMERSION HEATER(S)
Before removing the immersion heater(s) the unit
must be drained. Ensurethewater, electricalsupply
and boiler are OFF before draining. Attach a
hosepipe to the drain cock having sucient length
to take water to a suitable discharge point below the
level of the unit. Open a hot tap close to the unit
and open drain cock to drain unit.
DIRECT UNITS
Switch on electrical supply to the immersion
heater(s) and allow the Potterton Gold to heat up to
normal working temperature (60ºC recommended,
approximately graduation 4 on the thermostat). If
necessary the temperature can be adjusted by in-
serting a at bladed screwdriver in the adjustment
knob on top of the immersion heater thermostat
and rotating.
The adjustment range 1 to 5 represents a tempera-
ture range of 10oto 70oC. Check the operation of
thermostat(s) and that no water has issued from
the expansion relief valve or temperature/pressure
relief valve during the heating cycle.
INDIRECT UNITS
Openthecover(s)totheimmersionheaterhousing(s)
and disconnect wiring from immersion heater(s)
thermostat(s).Removethermostat bycarefully pulling
outwards. Remove thermostat capillary sensors from
the pockets on the immersion heater. Unscrew
immersion heater backnut(s) and remove immersion
heater from the unit. A key spanner is supplied
with the POTTERTON GOLD cylinder unit for easy
removal/tightening of the immersion heater(s).
Over time the immersion heater gasket may become
stuck to the mating surface. To break the seal insert
a round bladed screwdriver into one of the pockets
on the immersion heater and gently lever up and
down.
Carefully remove any scale from the surface of the
element(s). DO NOT use a sharp implement as
damage to the element surface could be caused.
Ensure sealing surfaces are clean and seals are
undamaged, if in doubt t a new gasket
(part number 95 611 822).
Replace immersion heater(s) ensuring the lower
(right angled) element hangs vertically downwards
towards the base of the unit. It may be helpful to
support the immersion heater using a round bladed
screwdriver inserted into one of the thermostat
pockets whilst the backnut is tightened. Replace
thermostat capillaries into pocket. Replace the
immersion heater thermostat by carefully plugging
the two male spade terminations on the underside
of the thermostat head into the corresponding
terminations on the element. Rewire, check, close
and secure immersion heater housing cover(s).
EXPANSION VESSEL CHARGE PRESSURE
Remove the dust cap on top of the vessel. Check the
charge pressure using a tyre pressure gauge. The
pressure(withsystemde-pressurised)shouldbe3.5bar.
If it is lower than the required setting it should be
re-charged using a tyre pump (Schrader valve type).
DO NOT OVER-CHARGE. Re-check the pressure and
when correct replace the dust cap.
RE-COMMISSIONING
Check all electrical and plumbing connections are
secure. Close the drain cock. With a hot tap open,
turn on the cold water supply and allow unit to
rell. DO NOT switch on the immersion heater(s) or
boiler until the unit is full. When water ows from
the hot tap allow to ow for a short while to purge
air and ush through any disturbed particles. Close
hot tap and then open successive hot taps in system
to purge any air.

15
When completely full and purged check system for
leaks. The heating source (immersion heater(s) or
boiler) can then be switched on.
USER INSTRUCTIONS
WARNINGS
IF WATER ISSUES FROM THE TEMPERATURE/
PRESSURE RELIEF VALVE ON THE POTTERTON
GOLD CYLINDER SHUT DOWN THE BOILER. DO
NOT TURN OFF ANY WATER SUPPLY. CONTACT A
COMPETENT INSTALLER FOR UNVENTED WATER
HEATERS TO CHECK THE SYSTEM.
DO NOT TAMPER WITH ANY OF THE SAFETY
VALVES FITTED TO THE POTTERTON GOLD
SYSTEM. IF A FAULT IS SUSPECTED CONTACT A
COMPETENT INSTALLER.
BENCHMARK
The POTTERTON GOLD cylinder is covered by the
Benchmark Scheme which aims to improve the
standards of installation and commissioning of
domestic heating and hot water systems in the
UK and to encourage regular servicing to optimise
safety, eciency and performance.
Benchmark is managed and promoted by the
Heating and Hotwater Industry Council. For more
information visit www.centralheating.co.uk.
Please ensure that the installer has fully completed
the Benchmark Checklist ( Page 19 and 20 ) of this
manual and that you have signed it to say that
you have received a full and clear explanation of its
operation.The installeris legallyrequiredtocomplete
a commissioning checklist as a means of complying
with the appropriate Building Regulations (England
and Wales).
All installations must be notied to Local Area
Building Control either directly or through a
Competent Persons Scheme. A Building Regulations
Compliance Certicate will then be issued to the
customer who should, on receipt, write the
Notication Number on the Benchmark Checklist.
This product should be serviced regularly to
optimise its safety, efficiency and performance.
The service engineer should complete the relevant
Service Record on the Benchmark Checklist after
each service.
The Benchmark Checklist may be required in the
event of any warranty work and as supporting
documentation relating to home improvements
in the optional documents section of the Home
Improvements Pack.
TEMPERATURE CONTROLS – DIRECT UNITS IMMER-
SION HEATER(S)
A combined adjustable thermostat and thermal
cut-out is provided for each immersion heater. The
thermostat is factory set to give a water storage
temperature of approx. 55oto 60oC. Access to the
thermostat can be made by opening the immer-
sion heater cover - DISCONNECT THE ELECTRICAL
SUPPLY BEFORE OPENING THE COVER(S). Tempera-
ture adjustment is made by inserting a at bladed
screwdriver in the slot on the adjustment disc on
top of the thermostat and rotating. The adjustment
range 1 to 5 represents a temperature range of 10o
to 70oC (60oC will be approximately position 4). If in
any doubt contact a competent electrician.
DO NOT bypass the thermal cut-out(s) in any
circumstances.
TEMPERATURE CONTROLS - INDIRECT UNITS (Fig. 7
Page 10)
The POTTERTON GOLD cylinder units are fitted
with an indirect thermostat and thermal cut-out.
These controls must be wired in series with the 2
port motorised zone valve supplied to interrupt the
ow of primary water around the heat exchanger
coil when the control temperature has been
reached. The controls are located within the lower
terminal housing along with the immersion heater
thermostat. The thermostat is factory set to give a
water storage temperature of approx. 55oto 60oC.
Access to the thermostat can be made by opening
the terminal housing cover - DISCONNECT THE
ELECTRICAL SUPPLY BEFORE OPENING THE
COVER. Temperature adjustment is made by
inserting a at bladed screwdriver in the adjustment
knob and rotating.The minimum thermostat setting
is 10oC. The adjustment range 1 to 5 represents
a temperature range of 30oto 70oC (60oC will be
approximately position 4). If in any doubt contact a
competent electrician.
An immersion heater is also provided for use should
theindirectheatsourcebeshutdownforany purpose.
The immersion heater control temperature is set
using the immersion heater thermostat.
DO NOT bypass the thermal cut-out(s) in any
circumstances.
FLOW PERFORMANCE
When initially opening hot outlets a small surge in
ow may be noticed as pressures stabilise. This is
quite normal with unvented systems. In some areas
cloudiness may be noticed in the hot water. This is
due to aeration of the water, is quite normal and
will quickly clear.

16
OPERATIONAL FAULTS
Operational faults and their possible causes are
detailed in the Fault Finding section of this book. It
is recommended that faults should be checked by
a competent installer.
The air volume within the expansion vessel will
periodically require recharging to ensure expanded
water is accommodated within the unit. A discharge
of water INTERMITTENTLY from the expansion
valve will indicate the air volume has reduced to
a point where it can no longer accommodate the
expansion.
FAULT FINDING & SERVICING
IMPORTANT
•After servicing, complete the relevant
ServiceIntervalRecordsectionoftheBenchmark
Checklist located on page 19 and 20 of this
document.
•Servicing should only be carried out by
competent persons in the installation and
maintenance of unvented water heating
systems.
•Any spare parts used MUST be authorised
POTTERTON GOLD parts.
•Disconnect the electrical supply before
removing any electrical equipment covers.
•NEVER bypass any thermal controls or
operate system without the necessary
safety valves.
•Water contained in the POTTERTON GOLD
cylinder may be very hot, especially following
a thermal control failure. Caution must be
taken when drawing water from the unit.
SPARE PARTS
A full range of spare parts are available for the
POTTERTON GOLD cylinder range (See Table 4 Page
17 ). Refer to the technical data label on the unit to
identify the model installed and ensure the correct
part is ordered. You will need to quote the serial
number, which is printed on the data label.
FAULT FINDING
The fault nding chart (Table 5 Page 18) will enable
operational faults to be identied and their possible
causes rectified. Any work carried out on the
POTTERTON GOLD cylinder unvented water heater
and its associated controls MUST be carried out by
a competent installer for unvented water heating
systems. In case of doubt contact service support
(see contact details on back page).
WARNING
DO NOT TAMPER WITH ANY OF THE SAFETY VALVES
OR CONTROLS SUPPLIED WITH THE POTTERTON
GOLD CYLINDER AS THIS WILL INVALIDATE ANY
GUARANTEE.

17
Table 4: Spares
Fig. 11: Spares Diagram
12
4
17
19
324 21 20 17
1416
.oNtraPnoitpircseD
Imme r s io n h e a t e r (lo w e r ) 9 5 606 9 6 1
Imme r s io n h e a t e r (u ppe r) 9 5 606 9 6 2
Imme r s io n h e a t e r g a s ke t 9 5 611 8 2 2
Imme r s io n h e a t e r b a c knut9 5 607 8 6 9
Imme r s io n h e a t e r ke y s p a nne r 9 5 607 8 6 1
Tund is h 9 5 605 8 3 8
E x p a n s io n v a lv e c a r tr idge - 6ba r 9 5 605 8 6 4
E x p a n s io n v a lv e co mp le t e - 6ba r 9 5 607 0 3 0
C o ld w a t e r c o m b in a t io n v a lv e
c o m p le t e 9 5 605 0 4 7
C o ld w a t e r c o mb in a t io n v a lv e b o d y 9 5 605 0 4 8
P r e s s u re re d u c in g v a lv e c a r t ridge
3 . 5 b a r 9 5 607 0 2 9
T
e mp e ra t u re /P re ssu r e R e lie f Va lv e 9 5 605 8 1 0
E x p a n s io n v e s s e l 12 lit re (100 , 1 20
a n d 150 lit r e m o d e ls ) 9 5 607 8 6 3
E x p a n s io n v e s s e l 18 lit re (170 a n d
210 lit r e m o d e ls ) 9 5 607 8 6 4
E x p a n s io n v e s s e l 24 lit re (250 a n d
300 lit r e m o d e ls ) 9 5 607 6 1 2
C o mb in e d t h e rm o s t a t a n d t h e r ma l
c u t -o u t 9 5 612 0 2 6
T e r min a l c o v e r 9 5 614 0 94
A c ce s s o r y kit (d ir e c t a n d w it h o u t
e x p a n sio n v e s se l) 9 5 607 9 6 9
In d ir e c t t h e r mo s t a t 9 5 612 6 9 7
In d ir e c t t h e r ma l c u t -o u t 9 5 612 6 9 8
Mot o r is e d v a lv e 2 p o rt 9 5 605 0 4 9
T e r min a l h o u s in g 9 5 614 0 9 0
4 W a y t e rmin a l blo ck 9 5 607 9 0 2
A c ce s s o r y kit (in d ir e c t a n d w it h o u t
e x p a n sio n v e s se l) 9 5 607 9 6 8
Blanking Plate Assembly 9 5 605 881
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25

18
Table 5: Fault nding chart
Table 6: Standing heat losses (based on an ambient air
temperature of 20oC and a stored water temperature
of 65oC)
HEAT LOSS ENVIRONMENTAL
INFORMATION
POTTERTON GOLD products are manufactured from
many recyclable materials. At the end of their useful life
they should be disposed of at a Local Authority Recycling
Centre in order to realise the full environmental
benets.
Insulation is by means of an approved CFC/HCFC free
polyurethane foam with an ozone depletion factor of
zero.
per day
(kWh/24h)
per year
(kWh/365d)
120 1.47 537
100 1.14
150 1.70 621
170 1.92 701
210 2.30 840
Standing Heat Loss
Nominal
Capacity
(litres)
250 2.22
300 2.52
811
920
416
While the following Checklist can be used for any installation covered by its description, only appliances
manufactured by Scheme Members will be covered by the rules and requirements of the Benchmark Scheme.
YDEMERESUACELBISSOPTLUAF
1. M ains s u pp ly o.
2. S t rainer bloc k e d.
and c lea n (s e e Page 13).
3. C o ld W a te r C o m b inat ion
V alve inc orre c tly tte d.
3 . C h ec k and re t as req u ire d .
1. DIRECT imme rs ion hea ter
not s w itc hed on.
1 . C h ec k and s w i tc h o n.
2. DIRECT imme rs ion hea ter
therm a l c ut -o ut has ope rated.
2. C hec k . R es e t by p us hin g but to n.
3. IN D IR E C T p ro g ra mmer s et
t o C e n tra l H e a tin g o nly .
3. C he c k . S e t to a D om e s tic H ot W a ter
pro g ramme.
4. IN D IR E C T boiler n ot
w o rk in g.
4 . C h e c k boiler op eration. If fault is
suspected c on s ult bo iler m an ufa c tu re r's
in s tru c tions .
5. IN D IR E C T t h erm a l c u t-o u t
has o pera ted .
5. C hec k . R es e t b y pu s hing but to n o n c u t-
out. (Fig. 10 Page 13 ).
Ch ec k op eration o f in direc t therm o s tat.
6. IN D IR E C T m o t o ris e d va lve
not c o nn ec t ed c o rrec t ly .
6 . C h e c k w iring and/o r p lu m bin g connections
to m o toris e d valve (s e e Page 12).
1. IN TE R M ITTE N TL Y
E x p ans io n V es s e l c harg e
pre ssu re h as re d uc ed b elo w
3.5bar.
1. S e e M ainte na nc e s e c tion fo r re-c h argin g
pro c ed ure .
2. C O N TIN U A LL Y
a. C o ld W a te r C o m b inat ion
V a lve P res s u re R edu c er n ot
w ork ing c o rre c tly .
2 a. C hec k p re s s u re from C old W a ter
C o m bin a tio n V a lve. If greater than 3.5b ar
rep la c e P re s s ure R ed uc er c art ridge.
b. E x p an s ion V a lve s e at
dam a ged .
2 b. R e m o ve E x pans io n V alve c a rtrid ge .
C he c k c on ditio n o f s e at. If nec es s a ry t
new E x pa n s io n V alve c art rid g e.
W ater d is c harg es from
T&P Re lie f V alve
1. The rm al c ontro l fa ilu re
N O TE w a te r w ill b e very ho t.
1 . S w itc h o  pow e r to immers ion h ea te r(s )
a nd s h u t d ow n b oile r. D O N O T tu rn o 
w a te r s upp ly . W h en d ischa rge s top s
c heck a ll th erm a l c on tro ls , replac e if fa ulty .
M ilk y w a t er
1. O x y g e n at e d w a t er.
re le as e s o x y g en b u b bl es w h en o w in g. Th e
milk in ess w i ll d is a ppear after a s hort w h ile .
N o h o t w a t er o w
W at e r from hot taps is c o ld
W ater d is c harg es from
E x pa ns io n V a lve
1 . C h e c k and op en s top c oc k .
2. Tu rn o  w a ter s upp ly . R em ove s t rainer
1. W a te r from a p re s s uris e d s y s t em

19

20